Gas-shut-off device



J. W..CHRISTIAN.

GAS SHUT-OFF DEVICE.

APPLICATION man DEc.15,192o.

l,402837. l Patented Jan. l.10, 1922.

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/7 zvezat t ma@ STATES PATENT oFF-ICE.

JOSEPH W. CHRISTIAN, or HAVEEIIILI., MASSACHUSETTS.

GAS-sIIUT-OEE DEVICE.

Specification of Letters Patent. f Patnted Jain. 10, 1922.

. Application filed-December 15, 1920.v Serial No. 430,898. Y

sachusetts, have invented an Improvement in GrasShut-0ff Devices,`of which the following is a Specification. Q

This invention'relates to devices for automatically shutting off the gas to the burner of a water heater', when used in `connection with a domestic boiler, and has for object to provide means whereby, when the burner is accidentally permitted to burn too long, so that nearly all the water in the boiler becomes heated close to the boiling point, or to a point such that there would be danger of bursting of the boiler', the gas supply to the burner will be automatically cut off. p

More specically my invention has for its object to provide an improved means for securing` the result above described, which issimple in construction and positive and reliable in operation and which is adapted to be applied to a water heating system already installed. y

l accomplish these objects by providing the construction hereinafter described and ydisclosed in the accompanying drawings in which Fig. 1'is a` diagrammatical view, illus-- trating the application of my invention to a domestic water heating system.

Figs. 2 and 3 are central longitudinal sections'of the gas shut-off valve.

Fig. l is a sectionalV view, at line L -4 of Fig. 2.

Fig. 5 is a longitudinal sectional view of` the fusible plug fitting.

.i irldb ln Fig. 1 a;V iagplanid Ployed dOHiLMl 'litl villini). illustrated, in connectinwith the autocommonly emmatically operating apparatus which I prefdicated, said plug comprising a tubular fit-` ting 6. which is screwed into, or otherwise Secured in theV side of the boiler, and a short tube T, which is screwed into the inner end of the fitting, so that it projectsinto the water @heating `system is K boiler, the passageway therethrough being filledwith .a plug 8-of fusible metal, which lsadapted to melt at approximately 2000 F.

A pipe-9 isconnected to the outer endof the fitting 6 and leads tothe automatic releasing device for thegas shut off` hereafter described.

The gas,jor other fuel, is supplied to theburner of the rheater 3 through a pipe 10, and

esl

a yvalve lcasing 11 islocated in Said pipe, so

thatthe gas liows through the passageway 12 therethrough. A piston valve 13 is arranged to control said passageway and is provided with a stem 14, which extends into a bonnet 15, threaded on the valve casing, said stem passing through a packing washer 16, which is clamped between the bonnet and casing. A spring 17 is arranged between the washer 16, which rests against the end of the bonnet 15, and the end of the piston 13,-

so that said spring tends to move thepiston to closed position. A stem extension 18 is connectedat one end to the stem 1 4, and has avalve disk 19 on its opposite end, which is adapted to seat against a shoulder 20,

formed about a passage v21 through the bony net, said passage extending longitudinally thereof land, then transversely, and ybeingl connected to a pipe 22, which in practice will be connected to a sewer, or other suitable waste outlet. f y

A cross bar`23 is connected by fusible solder to the vopposite side of the valve disk 19,4

fromthe stemlS, said bar being connected while the valve isin the open position, and` being oflsuiiicie'nt length to engage the end of the bonnet and hold the valve in open position' against the action of spring 17 ,f as shown in Fig. 2. A nipple 24 is connected at "one `end to. the end of the bonnet and at the opposite end to the pipe 9. y

Thefvalve 13 beingset in the position of Fig. 2,-and the parts being arranged as above described, the operation isas follows: Vhen the heater has been operated for vsuch a length of time that the temperature of the water in the boiler at the level of the fitting 6 is raised nearly to the boiling point, or to such Va point that there is danger of bursting, Vthev plug `8 will become fused, so that water-from the boiler will flow through pipe 9 intothe Avalve bonnet, through passage 21 and into the waste pipe 22, flow past the valve disk 19 bein I permitted, as the bore of the outer portio of the bonnet is of substantially greater diameter than that of the Icoy y Y. disk and the retaining bar 23 does not maf terially obstruct this flow.

The hot Water thus comes in direct contact with the solder which connects' the bar to the disk 19, and the fusing point of Which isY such that it will be fused thereby even .A

though the temperature of they Water is considerably lower than that required t o fuse i the plug 8. As soon as the solder, which rev tains the valve in open position, fuses, 'the' springlvivill act toV move the valve 13 vto A closed position, as shown in Fig, shutting ofi" the vflovv of gas to the burner and at the gasvalve, Whenreleased, is assisted by the f plosion, and that the boiler cannot be usedV impact andpressure of the Water against the disk 19, and, infact, the construction permits the entireomission of the spring 17, particularly ifthe space provided for the escape of Water past the disk is suitably restricted. L ,y

, 1f the `spring 17 were omitted, the cross bar 28 might also be omitted as there would be Vno action ,tending to close 4the shut-off valve, unless thevplug 8 should become fused,

so thatthewater Would be admitted'to the nipple 24.

In case the cross bar is employed, Which is; preferablathe provisionof a construction permitting the water from the boiler to flow past the fusible. solder, which .retains the cross bar 23 in position,^is especiallydesirable, as it insures the application of Water at the boiler pressure and permitting cold Water to flow into the boiler in case the Vgas shutoff valve should sticlrand not be closedbyV Vthe action of the spring and the Water pressure, or in casethe solder which retains the cross bar should not be fused. Y j

c It will be understood that the apparatus is designed tooperate only'in caseof special emergency, and When there is dangerof eX- again until theWhole apparatus has been reset. y

I-claim:

1L In a Water-,heating system, a boiler a heater therefor, a fuel burner for saidY heater and a fuel kconductor leading to said burner,

a shut-offvalve for said conductor,meansy normally actuated .to `rnolve said valve to closed position, fusible holding means Yfor retaining said valve in open position, a Water connection leading from the boiler to a Waste outlet and in which Y said fusible holding meansare arranged, a fusible plug for clos- Y ing said connection at its inlet. arrangedto befusedivhen the boQirv temperature is raised'to a predetermii'd" point, to permit the Water from the boiler to pass into contact with said fusible holding means and cause said valve to Vbe released, and means arranged to be actuated by movement ofpsaid *valvey to lclosed position to close said Water connection.

2, In aivater heating system, a boiler,a

heater therefor, a fuel burner for said heater and a fuel conductor leading to said burner, a shut-off valve for said conductor, normally actuated to be moved'to closed position, sible holding means for retaining said valve in'openY positionjal chamber in VWhich said holding means is located, a pipe leading from the boiler to said chamber and a Waste outlet leading therefrom, and temperature ycontrolled means normally closing said pipe 'and' .adapted toopen the same When the boiler temperature reaches a predetermined point,

topermit the Water from the boiler to pass through said'chamber into contact With said holding means. v Y v 3. ln a water heating system, a boiler, a heater therefor, a fuel burner forsaid heater 'and afuel conductor leading-to said burner,

ashut-off valve for said conductor, normally actuated to 4be ymoved to closed position, fusible holding `means for retaining said valve in Vopen position, a chamber in Which said holding means is located,y a vpipe leading from the boiler to said chamber and a Waste outlet leading therefrom, and temperature controlled means normally closing said pipe and adapted to open the same when the boiler i temperature reaches a" predetermined point,

to permitthe discharge of Water` from the I y n boiler to said chamber, thereby torfuseV said nearly boiler temperature thereto.` This construction also provides a means of relieving holding means and permit closure of said valve, and means connected to said, valve arranged to prevent the dischargeV of Water from said chamber When the valve is lin'its closed position. Y j

45. In a Water heating system, a boiler, a heater therefor, a fuel burner for said heater and a fuel conductor leadingto said burner,

a shut-offvalve for said conductor havingV a stem, aspring arranged to move said valve `toV closed position, a casing having 'a pas- Y .o rim f sagevvay therethroif ghgandintoxV Which said i .v Lua i i r'..- stem extends, a rfefaining) bar liaving a fusi ble connection stlim and arranged to engage said casing to hold said valve in open position, means on said stem arranged to seat in said casing, to close the passageway therethrough inthe closed, position'of said thereto from the boiler and having a nor-V iio mally open Waste outlet leading therefrom,

nieans normally olosinfr said pipe arranged through the pipe to said Chamber when the Water at the pipe entrance reaches a predetermined temperature, and means, in said ehainber,` arranged to be operated by the action or the Water flowing through said oham bei' to said outlet, to move said valve to its closed position.

6. ln. a Water heating system, aboiler, a heater thereior having a fuel burner and a iuel conductor leading to said burner, a normail),v open shut-oil valve in said conductor,

Va Water chamber having an inlet at one end and a normallyY open Waste outlet at the opposite end, a stem connected to said valve and extending into said chamber, a disk on said stem Constructed and arranged to permit restricted flow oit/Water through said chamber to said outlet when in normal position and movable from said position toivard said outlet to move said valve to closed position, a pipe leadingfrom the boiler to said f-hambei' inlet and means for normally elosing said pipe adapted to be Jfused, when the temperature oif the kWater in the boiler reaches a predetermined temperature, to permit the iioiv ot water ifromthe boiler through said pipe and ychamber to said outlet and to applypressure to said dish Ato move the saine i in a direction to close said valve.

7. ln a Water heating'system, a boiler,

heater therefor havinv a fuel burner and a fuel Conductor leadii'ig` to said burner, a normallliY open shut-oil valve in said conductor, a water ohainberhaving an inlet at one end and a normally open outlet at the opposite end, a stem connected to said valve and ei;- tending into said Chamber, a ydisk on said stom loosely fitting said chamber to permit a restrieted tloiv of Water therethrough When in normal position and movable from said position toward said outlet to move said valve to closed position and to close said outlet when the valve is in closed position, a

pipe leading from'the boiler to said Chamber e inlet and means v`for normally closing said pipe adapted to be fused When the Water in tlieboiler rear-hes a predetermined temperature, to permit the flow of Water from the boiler through said pipe and chamber to said outlet and to apply pressure to said disk to more the same in a direction to close 'said valve.k i l S. ln a Water heating;` system, a boiler, a heater therefor having a Jfuel burner and a iuel Conductor leading to said burner, a normally open shut-oil valve in said conductor, a Water chamber having` an inlet at one end and a normally open outlet at the opposite end, a stem connected to said valve and extending into said Chamber, a disk on said stem loosely litting said Chamber to permit afrestrioted flow of vWater therethrough when in normal position, and arranged, when e moved toward the outlet end oi the chamber,

to cause Closingmovement of saidvalve, fusible holding means in said chamber for t retaining said valve in said normal position,

spring-actuating means for moving said y valve 'from saidrpositionto Closed position when released by said holding means, a pipe leading from the boiler to said chamber iiilet, and means for normally closing said pipe l holdin@h means and aiil iressure to said C dish ina direction to'move the valve to closed position.

ln testimony whereof l have signed name to this specification.

JOSEPH W. CHRISTlAN; 

